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The paper discusses the problems arising during quality control of the raw materials (e.g., borehole fluid, crude oil, and oil–water emulsions) in the processes of their production, conditioning for transport, and processing. It is shown, that the existing means of express control of oil quality have low accuracy and insufficient speed of measuring oil characteristics. To ensure the quality of oil and purity of the separated ballast water, their additional purification is necessary. To perform the express control of oil characteristics (properties) during its production, conditioning and transportation, a proton magnetic resonance relaxometer and a multiparametric flow-through measuring complex with a representative sampling system have been developed. A method of nuclear (proton) magnetic resonance relaxometry, configuration and functioning algorithm of the measuring complex, as well as the structure and operation of the proton magnetic resonance relaxometer are described. Equations describing technical, electromagnetic, and circuit parameters of the relaxometer have been obtained. The relaxometer underwent metrological testing as part of the measuring complex during express control of the properties of oil samples. The following measurement errors of the characteristics of borehole fluid, crude oil, oil–water emulsions, and ballast water separated from oil were obtained: ±1% (relative error) for water content in oil in the range from 0 to 100%; ±0.2 mg/L for salt concentration in water in the range from 0 to 10 g/L; ±0.3% (relative error) for sulfur content in oil in the range from 0.1 to 8.0 abs.%; ±1.47 kg/m3 for oil density in the extended range from 700 to 1100 kg/m3; and ±0.13 mm2/s for kinematic viscosity of oil in the range from 0 to 350 mm2/s. The oil samples were characterized using analytical laboratory techniques. The introduced measuring complex enables data verification based on several parameters obtained using proton magnetic resonance relaxometry. The developed flow-through measuring complex can be used when controlling a multifunctional automated digital smart well, as well as equipment for separating water from the oil–water emulsions and treating produced water. [ABSTRACT FROM AUTHOR]

Today, an urgent and unresolved issue is the study of transport operations that are used in the agricultural sector, because there is a problem when studying the movement of a machine-tractor unit with trailed or semi-trailer units. This is directly related to the increase in energy saturation of wheeled tractors and, as a result, an attempt to maximize vehicle performance. The study of transport work in the transportation of liquid cargo is of great interest, where an increase in cargo transportation leads to significant instability in the operation of a wheeled tractor and a tractor tank (which is devoid of internal partitions) due to natural vibrations of the liquid. This process leads to longitudinal and lateral instability, contributes to an increase in both dynamic characteristics and emergency situations (there is an effect on the smoothness of movement, vibration load, handling and stability of the vehicle, increasing the dynamic load of the undercarriage, etc.). Therefore, to confirm the theoretical aspects of the influence of fluid oscillations in the tractor tank, experimental studies are necessary. The experimental research methodology presented in this article will allow us to determine the dynamic characteristics during transportation of trailed and semi-trailer tractor tanks during steady-state movement, as well as in transient operation modes. The practical significance of the work is to obtain experimental data on the accelerations of the studied objects at different height filling of the liquid level in the tanks.

Purpose. The creation of a measuring device for determining the impedance of the grounding of lightning arresters and supports of overhead lines under the influence of aperiodic pulses with the parameters 1.2/50 μs, 8/20 μs and 10/350 μs. Methodology. For this purpose, electrical engineering theory, transient modeling software and natural modeling methods are used. Results. The parameters of the electrical circuits of the additional forming unit were determined to create lightning current pulses with parameters of 10/350 μs using the IK-1U measuring complex. According to the simulation results, a layout of the forming unit in the form of an attachment and the IK-1U complex with the upgraded power supply system were created. Oscillograms of the front and pulse duration are obtained. The specified model was tested when performing electromagnetic diagnostics of the state of the RFP for more than 100 operating electrical substations. Originality. The measuring complex IK-1U was improved, which made it possible to determine the impulse impedance of the grounding device of lightning arresters when exposed to a current of 10/350 μs, 8/20 μs and of voltages 1.2/50 μs. Practical value. Upgraded device allows measurements in accordance with modern international requirements.

The development of metamaterials has led to the search and selection of effective methods for radio wave nondestructive testing of their electrophysical parameters. The existing approaches to testing, based on the recovery of the effective electrophysical parameters of metamaterials from the reflection and transmission coefficients of an electromagnetic wave, have low reliability and do not provide the local inspection of the parameters. In this paper, we propose for the first time a radio-wave method for local inspection of complex dielectric and magnetic permeabilities, as well as the thickness of flat-layered samples of metamaterials on a metal substrate using surface electromagnetic waves of the microwave range. The method is based on solving the inverse problem of determining the effective electrophysical parameters of a metamaterial from the frequency dependence of the complex attenuation coefficient of the field of a surface electromagnetic wave excited in the sample under study. In this case, the electrophysical parameters of the metamaterial are represented in the form of parametric frequency functions in accordance with the Drude–Lorentz dispersion models, and the solution of the inverse problem is reduced to minimizing the objective function constructed from the discrepancy between the experimental and calculated theoretical values of the attenuation coefficients of the surface electromagnetic wave field on a grid of discrete frequencies. The structure of the measuring complex that implements the proposed inspection method is presented. A sample of a flat-layered metamaterial based on SRR elements with a region of negative refraction in the frequency range of 10.06–10.64 GHz was investigated for the numerical and experimental verification of the method. Experimental verification has shown that the local values of the effective electrophysical parameters of the studied metamaterial differ from the calculated ones by no more than 10%. [ABSTRACT FROM AUTHOR]

Practical application of the radio-holographic method for measuring the characteristics of antennas, especially when conducting acceptance testing of systems, requires an adequate assessment of the errors in the recovery of long-range characteristics. These errors appear to be a superposition composed of various sources, having different nature, different time characteristics and different degrees of influence on the final result. The purpose of this work was the development of a practical technique for determining the influence of random errors in measuring the amplitude-phase distribution of the field of the antenna required for the accuracy of restoring long-range characteristics (primarily the antenna pattern) of the antenna, the proposed technique being based only on processing the experimental results obtained with this measuring complex.A practical method for determining the influence of random errors in measuring the amplitude-phase distribution of the field of the antenna under study on the accuracy of restoring its long-range characteristics (primarily the directional pattern) on the basis of correlation and spectral analysis has been developed and experimentally confirmed. The main advantage of the developed method in comparison with the use of mathematical modeling is that the estimation of the accuracy of the reconstruction of the directivity diagrams is based on the results of processing experimental data obtained on a specific measuring complex and does not a priori impose any preliminary requirements on the statistical parameters of errors. The developed procedure for estimating the influence of random errors can be used to develop a methodology for metrological certification of measuring systems as measuring instruments.

Directional patterns measurement of antennas is carried out by the methods of far and near zone. Measurements in the far zone are straightforward; however they have a number of disadvantages. Near zone measurement methods are free from measurement shortcomings in the far zone, but it requires complex and expensive equipment for its implementation.Earlier, the authors have developed a concept of hardware and software modular design complex to determine antenna system characteristics as per measurements in the near zone. This concept assumes creation of a universal measuring complex to investigate various types of antenna systems with any type of measurement surface (plane, cylinder, sphere) in order to solve a wide range of applied problems. The purpose of this work lies in practical implementation of a variant of this measuring complex for measurement along the plane and determination of its metrological (hardware and software) capabilities.A working experimental sample of hardware and software complex for measuring the characteristics of antenna systems that realizes a radio-holographic method for measuring along a plane has been developed, created and practically tested. A preliminary estimation of errors in amplitude and phase measurements in the dynamic range of 45 dB and a comparison of the characteristics of several types of antennas measured in far and near zones have been made. Algorithms have been developed, a software for processing, storing and graphical display of measurement results has been created.

In this paper, the hardware-software high resolution measuring system for studying the spatial and spectral distributions of the radiation intensity of a magnetron discharge is described. The emission spectra are recorded and processed for subsequent determination of the temperature and density of plasma electrons. These parameters are calculated on the basis of a technique suggesting the absence of ionization equilibrium and the Boltzmann distribution of populations of energy levels of the plasma-forming gas. The data on the electron density, atomic distributions by excited states, and the degree of their deviation from equilibrium in the entire volume of the discharge are presented. [ABSTRACT FROM AUTHOR]

Measuring the amplitude-phase distribution of the radiation field of complex antenna systems on a certain surface close to the radiating aperture allows solving the problem of reconstructing the free-space diagram in the far field and also helps in determining the influence of various structural elements and defects of radiating surfaces on formation of directional diagram. The purpose of this work was to develop a universal hardware-software complex of a modular design aimed for determining the characteristics of wide range of antenna systems in respect of measurements of the amplitude-phase distribution of the radiation field in the near zone.The equations that connect the structure of radiation fields of the antenna system at various distances from it in planar, cylindrical and spherical coordinate systems as well as structural diagrams of the hardware part of measuring complexes have been analyzed.As a result, the concept of constructing a universal hardware-software complex for measuring the radiation field of various types of antenna systems with any type of measurement surface for solving a wide range of applied problems has been developed. A modular structure of hardware and software has been proposed; it allows reconfiguring the complex rapidly in order to measure the characteristics of any particular antenna system at all stages of product development and testing, and also makes the complex economically accessible even for small enterprises and organizations.

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Experimental study of underground polymer pipes under temperature effect is developed in this paper by the method of centrifugal modeling to study the process of polymer pipes elongation depending on the depth of laying and physical and mechanical properties of soil. The method is based on the use of centrifugal installation with PC and software. The experiments were carried out in a centrifuge with an effective radius of centrifuge rotation at a working scale of modeling n = 40. Experimental studies were carried out at various laying depths of the underground polymer pipes. In the process of conducting experiments, the polymer pipe model was subjected to various temperature influences. The temperature effect on the polymer pipe model was created using an electric spiral. As a result, it is established that the process of polymer pipes elongation over time under soil pressure and temperature factor has a non-linear character; the value of the absolute strain depending on the laying depth and the temperature factor may differ by several times.

More accurate navigation systems are always required for autonomous unmanned underwater vehicles (AUUV)s under various circumstances. In this paper, a measuring complex of a heavy unmanned underwater vehicle (UUV) was investigated. The measuring complex consists of an inertial navigation platform system, a Doppler lag (DL) and an estimation algorithm. During a relatively long-term voyage of an UUV without surfacing and correction from buoys and stationary stations, errors of the measuring complex will increase over time. The increase in errors is caused by an increase in the deviation angles of the gyro platform relative to the accompanying trihedron of the selected coordinate system. To reduce these angles, correction is used in the structure of the inertial navigation system (INS) using a linear regulator. To increase accuracy, it is proposed to take into account the nonlinear features of INS errors; an adaptive nonlinear Kalman filter and a nonlinear controller were used in the correction scheme. Considering that, a modified nonlinear Kalman filter and a regulator in the measuring complex are proposed to improve the accuracy of the measurement information, and modification of the nonlinear Kalman filter was performed through a genetic algorithm, in which the regulator was developed by the State Dependent Coefficient (SDC) method of the formulated model. Modeling combined with a semi-natural experiment with a real inertial navigation system for the UUV demonstrated the efficiency and effectiveness of the proposed algorithms.

More accurate navigation systems are always required for autonomous unmanned underwater vehicles (AUUV)s under various circumstances. In this paper, a measuring complex of a heavy unmanned underwater vehicle (UUV) was investigated. The measuring complex consists of an inertial navigation platform system, a Doppler lag (DL) and an estimation algorithm. During a relatively long-term voyage of an UUV without surfacing and correction from buoys and stationary stations, errors of the measuring complex will increase over time. The increase in errors is caused by an increase in the deviation angles of the gyro platform relative to the accompanying trihedron of the selected coordinate system. To reduce these angles, correction is used in the structure of the inertial navigation system (INS) using a linear regulator. To increase accuracy, it is proposed to take into account the nonlinear features of INS errors; an adaptive nonlinear Kalman filter and a nonlinear controller were used in the correction scheme. Considering that, a modified nonlinear Kalman filter and a regulator in the measuring complex are proposed to improve the accuracy of the measurement information, and modification of the nonlinear Kalman filter was performed through a genetic algorithm, in which the regulator was developed by the State Dependent Coefficient (SDC) method of the formulated model. Modeling combined with a semi-natural experiment with a real inertial navigation system for the UUV demonstrated the efficiency and effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]